Experimental analysis of horizontal ground heat exchanger

In this study, soil temperature variation around horizontal soil heat exchangers (HGHEs), which are widely used for ground-based heat pump (GSHP) systems, was experimentally determined. To determine temperatures and analyse the ground massif temperature changes in the HGHE area, an experimental set-up has been constructed for climatic condition of Çorlu Town located in the Marmara region of Turkey. The experimental results were obtained from 4 August to 14 October in cooling and transition season of 2015. In the experimental study, the soil temperatures at six points at different depths and intervals, and the HGHE inlet and outlet temperatures were measured. The energetic potential of the ground massif was evaluated for operation period and stop periods (night period and transition season). It has been observed that the amount of heat rejected to the soil decreased over time in the working period. The energy accumulated during the working period was not completely destroyed during the night period. But the soil has renewed itself in great measure during the transition season. It has been found that the potential of self-renewal of the soil around the middle pipes of the GHE is less when compared with the soil around the edge pipe due to thermal interaction.